Hummingbird party in Costa Rica… whose Latin names are these and why?

Once again American Ornithological Society supplement is out (here) and once again we are looking at what is new for Costa Rica, the country from where Lifer Nature Tours lead operations and hundreds of worldwide birders keep their updated life lists. So if you are one of those, you might like to read below about what is new with the 2020 AOS supplement.

The changes are quite simple for Costa Rican listers IF you only follow common English names but if you also enjoy Latin names, it becomes a bit more interesting:

ONLY TWO ENGLISH NAME CHANGED (here is where you need to get a pen and write a little side note in your bird book)

1- The new English name for Checker-throated Antwren (Epinecrophylla fulviventris) changes to Checker-throated Stipplethroat. The South American Classification Committee has changed the English names of all species in the genus Epinecrophylla from "Something" Antwren to the "Something" Stipplethroat. The rationale for this is complicated and derives largely from the problem created by multiple species splits in the genus that created severe English name problems.

This proposal went through three iterative modifications – like they said "a lot of work for something so trivial", but there was no easy way to avoid this, and the rationale was that as long as a change was needed, it was worth the effort to have the best outcome.

So basically they decided to make a change because "it has to be done" to fit what is happening in South America with these antwrens. Anyway Stipplethroat is a very cool name and I think we all should be happy to have our only "Epinecrophylla" to get adapted to their kind.

2- The Paltry Tyrannulet changes to Mistletoe Tyrannulet (Zimmerius parvus).

This popular and generally common species occurs in several separate populations that correspond to recognized subspecies but these populations required additional taxonomic recognition. So, although the proposal was more "aggressive" and included several splits, they ended up basically splitting the species into just two species for now: Guatemalan Tyrannulet in northern Central America and our new Mistletoe Tyrannulet. With a range of most of northern Honduras, eastern Nicaragua, Costa Rica, Panama, and a small part of Colombia bordering Panama.

The Mistletoe Tyrannulet (Zimmerius parvus) is common in gardens and forest edges, this one was taken in Arenal Volcano area by Juan Diego Vargas

If you, like us, enjoy the luxury of Latin names and want to invest some time understanding them, there are a few very interesting changes you might enjoy.

THE HUMMINGBIRD SOUP

Most changes follow two recent studies of the generic classification of the Trochilini or “Emerald hummingbirds” because there are numerous instances of incongruences with respect to the DNA-based phylogeny of this group (Stiles et al. 2017), and this is the largest major clade of hummingbirds, with over 100 species.

The changes are as follow in all genus (no English names were changed here):

The lovely Canivet’s Emerald changes his genus from Chlorostilbon to Cynanthus canivetii. This is super strange because the other "Chlorostilbon" does not change. So Garden Emerald will stay the same. So now two of the most similar looking hummingbirds (tell apart basically only by bill color and range) are both in different genwera! For me, this is hard to believe.

Two interesting moves are the Coppery-headed Emerald and the White-tailed Emerald. They both now belong to the same genus as Snowcap! So, now, both are Microchera cupreiceps and Microchera chionura accordingly .

Coppery-headed Emerald (Microchera cupreiceps) is one of the only 2 hummingbirds completely endemic to Costa Rica. This one was taken in Monteverde Reserve by Juan Diego Vargas.

Snowcap (Microchera albocoronata), a truly stunning beauty long considered monotypic due to its amazing colors, this one was taken at Tapir Valley, one of the top "new" birding attractions of the Tenorio Volcano area. Photo by Juan Diego Vargas

Do you see any similarity of these two above? well in DNA apparently they do and also the females are quite similar if you think about it.

Saucerottia hoffmanni Blue-vented Hummingbird.

Saucerottia cyanura Blue-tailed Hummingbird.

Saucerottia edward Snowy-bellied Hummingbird.

Blue-vented Hummingbird (Saucerottia hoffmanni), taken in the lower slopes of the Miravalles Volcano by Juan Diego Vargas early this year.

This new genus is quite interesting since it retains the old species name of the now disappeared Steely-vented Hummingbird (Amazilia saucerrotti) pictured above. These all three have some morphological similarities and kind of make sense. Particularly the first two. They all were in the Amazilia genus before.

Lepidopyga coeruleogularis changed to Chrysuronia coeruleogularis for the Sapphire-throated Hummingbird.

Two famous Amazilia changed to a resurrected genus call Polyerata and will be used in Blue-chested Hummingbird (Polyerata amabilis) and Charming Hummingbird (Polyerata decora).

Supposedly, our country endemic and one of the best birds of Costa Rica, the Mangrove Hummingbird, will also belong to this genus but this now left as "uncertain".

Mangrove Hummingbird (Amazilia boucardi*) is maybe one of the most unique hummingbirds of Costa Rica since is restricted to mangrove forest of Costa Rica on the Pacific Coast. This one ws taken in Guacalillo, Puntarenas by Juan Diego Vargas while feeding in a local garden.

And to finish with the hummingbirds two birds that seem to have nothing in common are grouped in the same genus:

Chlorestes candida White-bellied Emerald (formerly an Amazilia).

Chlorestes eliciae Blue-throated Goldentail (formerly a Hylocharis).

Is a shame for the Hylocharis because it makes a lot of sense with other Hylocharis in having that thick red bill.

ANTBIRDS GALORE

They also changed the genus in two antbirds, the first is Poliocrania exsul for Chestnut-backed Antbird. They noted, as additional support for separating Chestnut-backed Antbird because it differs in nest architecture from the other species in this clade.

The second antbird with a Latin name change is Dull-mantled Antbird to Sipia laemosticta. And here surprisingly, they didn't touch the Zeledon's Antbird (Myrmeciza zeledoni), to Hafferia zeledoni, as they suggested they still need further research for this and do not back up the decision taken by the South America Classification Committee they followed last year in moving the genus of this antbird. Apparently the Zeledon's Antbird refuses to leave his genus for the North American lists. This might produce some confusion in the future.

Zeledon's Antbird (Myrmeciza zeledoni), the male is entirely jet black. Taken in Arenal Volcano Sky Adventures Park by Juan Diego Vargas

Zeledon's Antbird (Myrmeciza zeledoni), the female is colored with rich brown. Taken in Arenal Volcano Sky Adventures Park by Juan Diego Vargas

OTHER CHANGES

Dendroma rufa Buff-fronted Foliage-gleaner.

This is an interesting case. It changes from the very nice Philydor genus. And the reason is that genetically is very distant to other Philydor. You can see in the graphic below how far apart are these two from other in the same genus and how they even come from a total different lineage. This is pretty interesting considering that the Buff-fronted Foliage-gleaner in Costa Rica is a separate subespecies and is one of the hardest foliage-gleaners of all the country (and we hope one day will be a separate species). So this taxonomy helps us suggest that this bird (and its whole group) belongs to a pretty special case one day we will understand much better.

Buff-fronted Foliage-gleaner (Dendroma rufa), the subspecies "panerythrum" is locally found from Costa Rica to the east of the Colombian Andes and it is one of the hardest furnarids in Costa Rica.

THE MISTAKEN MANAKIN

The White-crowned Manakin was long considered congeneric with other members of the genus Pipra, until Prum (1990, 1992, 1994) demonstrated that its display repertoire and syringeal morphology differ considerably from all other members of that genus. Subsequently, three different molecular phylogenies have all indicated that this manakin is more closely related to Club-winged Manakin than to other similar looking members.

Prum (1992) stated, without elaboration, that the name Dixiphia was available for this manakin based from a figure on a Plate from 1850 by Reichenbach (pictured below) and most people agree and moved the Manakin to this genus (an update in the 2019 AOS supplement). Of course,important for all of us that follow taxonomic updates is seeing that this manakin is changing its genus AGAIN this year. The reason make sense and it's kind of funny because it was all after Kirwan reported that this genus is all wrong because the Dixiphia of Reicheninbach does not apply to the Manakin, actually the drawing was intended to be, quite clearly, a male White-headed Marsh Tyrant (Arundinicola leucocephala) and was used without any explanatory text (see the image below).

Remarkably, even Linnaeus (1758: 191) had also confused this white-crowned Piprid with the completely white-headed water-tyrant, but fortunately after some diagnosis and references they cleared the confusion and realized that this name "Dixiphia" was not available and should not be use for the manakin.

This new paper goes over all this issue and designated a complete new genus to this certainly special and unique manakin; Pseudopipra. This genus is a very appropriate one since it basically means the "false manakin". Mostly because this is one of the very few manakins that among other special features does not have any modification in their wing feathers and for instance does not make any mechanical sound. Different than most other manakins.

Check out here to listen the sounds non-mechanical sound of the White-crowned Manakin in Costa Rica, from now on referred as Pseudopipra pipra.

Below you can see Detail from Plate LXIII of Reichenbach (1850) showing the bird that he named Dixiphia; all visible features are those of a male White-headed Marsh Tyrant instead of the manakin. But well, hey, is not too easy to guess since both species have entirely white crown and black and white drawing does not help, so I understand the confusion.

And finally the White-shouldered Tanager will be Loriotus luctuosus instead of Tachyphonus luctuosus. Another interesting change that make no sense but just to show us that the color we see means just nothing and we have to look more closely to DNA. Because this tanager always look very similar to White-lined and Tawny-crested tanagers and I will bet they were all part of the same group but apparently they are not and just happen to share color because it functions in the similar niches where they live.

AND FINALLY: THE FOREMOST ORNITHOLOGICAL MYSTERY OF COSTA RICA WAS REJECTED, AGAIN.

125 years ago, C.F. Underwood collected a strange hummingbird in the lower part of the Miravalles Volcano of Costa Rica. This hummingbird was originally labeled as Indigo-capped Hummingbird (a hummingbird endemic to a small area of Colombia), later on was reviewed again and was renamed as Amazilia alfaroana, an endemic hummingbird of Miravalles Volcano. BUT only one single specimen was collected so they kind of leave the discussion there. Recently Kirwan and Collar (2016) brought the issue back again and re examined the specimen just to conclude is not likely a hybrid and is nothing else present in the area, so it has to be a new endemic that is likely to be extinct. The proposal was presented to the AOS but was rejected (of course because they only have one sample and that sample is 125 years old). They clearly said that they required more data to accept the species in the list of bird of North America. The suggested name was Guanacaste Hummingbird, very appropriate and very exciting for all Costa Ricans.

The hope still exists for all of us birdwatchers to find a trace of the "foremost ornithological mystery of Costa Rica" as Stiles and Skutch referred to this specimen in their book.

In the image below you have figure 5 and 6 an image of dorsal and ventral views of two specimens of Indigo-capped Hummingbirds Amazilia cyanifrons (on right), from Colombia, compared to the holotype of Amazilia alfaroana (Guy M. Kirwan, Natural History Museum, London)

Figures 7 and 8. Dorsal and ventral views of two specimens of Steely-vented Hummingbird Amazilia saucerottei hoffmanni (on left), from Costa Rica, compared to the holotype of Amazilia alfaroana (Guy M. Kirwan, Natural History Museum, London)

The whole article for this description of the Guanacaste Hummingbird can be found here. Is specially good read if you, like me, enjoy believing in miracles and like to dream about the existence of this magical bird.